- Browse by Author
Browsing by Author "Overcoming Covid-19 Investigators"
Now showing 1 - 2 of 2
Results Per Page
Sort Options
Item BNT162b2 Protection against the Omicron Variant in Children and Adolescents(Massachusetts Medical Society, 2022) Price, Ashley M.; Olson, Samantha M.; Newhams, Margaret M.; Halasa, Natasha B.; Boom, Julie A.; Sahni, Leila C.; Pannaraj, Pia S.; Irby, Katherine; Bline, Katherine E.; Maddux, Aline B.; Nofziger, Ryan A.; Cameron, Melissa A.; Walker, Tracie C.; Schwartz, Stephanie P.; Mack, Elizabeth H.; Smallcomb, Laura; Schuster, Jennifer E.; Hobbs, Charlotte V.; Kamidani, Satoshi; Tarquinio, Keiko M.; Bradford, Tamara T.; Levy, Emily R.; Chiotos, Kathleen; Bhumbra, Samina S.; Cvijanovich, Natalie Z.; Heidemann, Sabrina M.; Cullimore, Melissa L.; Gertz, Shira J.; Coates, Bria M.; Staat, Mary A.; Zinter, Matt S.; Kong, Michele; Chatani, Brandon M.; Hume, Janet R.; Typpo, Katri V.; Maamari, Mia; Flori, Heidi R.; Tenforde, Mark W.; Zambrano, Laura D.; Campbell, Angela P.; Patel, Manish M.; Randolph, Adrienne G.; Overcoming Covid-19 Investigators; Pediatrics, School of MedicineBackground: Spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 (omicron) variant, which led to increased U.S. hospitalizations for coronavirus disease 2019 (Covid-19), generated concern about immune evasion and the duration of protection from vaccines in children and adolescents. Methods: Using a case-control, test-negative design, we assessed vaccine effectiveness against laboratory-confirmed Covid-19 leading to hospitalization and against critical Covid-19 (i.e., leading to receipt of life support or to death). From July 1, 2021, to February 17, 2022, we enrolled case patients with Covid-19 and controls without Covid-19 at 31 hospitals in 23 states. We estimated vaccine effectiveness by comparing the odds of antecedent full vaccination (two doses of BNT162b2 messenger RNA vaccine) at least 14 days before illness among case patients and controls, according to time since vaccination for patients 12 to 18 years of age and in periods coinciding with circulation of B.1.617.2 (delta) (July 1, 2021, to December 18, 2021) and omicron (December 19, 2021, to February 17, 2022) among patients 5 to 11 and 12 to 18 years of age. Results: We enrolled 1185 case patients (1043 [88%] of whom were unvaccinated, 291 [25%] of whom received life support, and 14 of whom died) and 1627 controls. During the delta-predominant period, vaccine effectiveness against hospitalization for Covid-19 among adolescents 12 to 18 years of age was 93% (95% confidence interval [CI], 89 to 95) 2 to 22 weeks after vaccination and was 92% (95% CI, 80 to 97) at 23 to 44 weeks. Among adolescents 12 to 18 years of age (median interval since vaccination, 162 days) during the omicron-predominant period, vaccine effectiveness was 40% (95% CI, 9 to 60) against hospitalization for Covid-19, 79% (95% CI, 51 to 91) against critical Covid-19, and 20% (95% CI, -25 to 49) against noncritical Covid-19. During the omicron period, vaccine effectiveness against hospitalization among children 5 to 11 years of age was 68% (95% CI, 42 to 82; median interval since vaccination, 34 days). Conclusions: BNT162b2 vaccination reduced the risk of omicron-associated hospitalization by two thirds among children 5 to 11 years of age. Although two doses provided lower protection against omicron-associated hospitalization than against delta-associated hospitalization among adolescents 12 to 18 years of age, vaccination prevented critical illness caused by either variant.Item Maternal Vaccination and Risk of Hospitalization for Covid-19 among Infants(Massachusetts Medical Society, 2022) Halasa, Natasha B.; Olson, Samantha M.; Staat, Mary A.; Newhams, Margaret M.; Price, Ashley M.; Pannaraj, Pia S.; Boom, Julie A.; Sahni, Leila C.; Chiotos, Kathleen; Cameron, Melissa A.; Bline, Katherine E.; Hobbs, Charlotte V.; Maddux, Aline B.; Coates, Bria M.; Michelson, Kelly N.; Heidemann, Sabrina M.; Irby, Katherine; Nofziger, Ryan A.; Mack, Elizabeth H.; Smallcomb, Laura; Schwartz, Stephanie P.; Walker, Tracie C.; Gertz, Shira J.; Schuster, Jennifer E.; Kamidani, Satoshi; Tarquinio, Keiko M.; Bhumbra, Samina S.; Maamari, Mia; Hume, Janet R.; Crandall, Hillary; Levy, Emily R.; Zinter, Matt S.; Bradford, Tamara T.; Flori, Heidi R.; Cullimore, Melissa L.; Kong, Michele; Cvijanovich, Natalie Z.; Gilboa, Suzanne M.; Polen, Kara N.; Campbell, Angela P.; Randolph, Adrienne G.; Patel, Manish M.; Overcoming Covid-19 Investigators; Pediatrics, School of MedicineBackground: Infants younger than 6 months of age are at high risk for complications of coronavirus disease 2019 (Covid-19) and are not eligible for vaccination. Transplacental transfer of antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) after maternal Covid-19 vaccination may confer protection against Covid-19 in infants. Methods: We used a case-control test-negative design to assess the effectiveness of maternal vaccination during pregnancy against hospitalization for Covid-19 among infants younger than 6 months of age. Between July 1, 2021, and March 8, 2022, we enrolled infants hospitalized for Covid-19 (case infants) and infants hospitalized without Covid-19 (control infants) at 30 hospitals in 22 states. We estimated vaccine effectiveness by comparing the odds of full maternal vaccination (two doses of mRNA vaccine) among case infants and control infants during circulation of the B.1.617.2 (delta) variant (July 1, 2021, to December 18, 2021) and the B.1.1.259 (omicron) variant (December 19, 2021, to March 8, 2022). Results: A total of 537 case infants (181 of whom had been admitted to a hospital during the delta period and 356 during the omicron period; median age, 2 months) and 512 control infants were enrolled and included in the analyses; 16% of the case infants and 29% of the control infants had been born to mothers who had been fully vaccinated against Covid-19 during pregnancy. Among the case infants, 113 (21%) received intensive care (64 [12%] received mechanical ventilation or vasoactive infusions). Two case infants died from Covid-19; neither infant's mother had been vaccinated during pregnancy. The effectiveness of maternal vaccination against hospitalization for Covid-19 among infants was 52% (95% confidence interval [CI], 33 to 65) overall, 80% (95% CI, 60 to 90) during the delta period, and 38% (95% CI, 8 to 58) during the omicron period. Effectiveness was 69% (95% CI, 50 to 80) when maternal vaccination occurred after 20 weeks of pregnancy and 38% (95% CI, 3 to 60) during the first 20 weeks of pregnancy. Conclusions: Maternal vaccination with two doses of mRNA vaccine was associated with a reduced risk of hospitalization for Covid-19, including for critical illness, among infants younger than 6 months of age.